EN19 | SAE4140 | DIN 1.7225 | 42Crmo4 | SCM440 ALLOY STEEL

EN 19 offers good ductility and shock resisting properties combined with resistance to wear. With these characteristics it is a popular high tensile engineering steel with a tensile of 850/1000 N/mm². At low temperatures EN19 has reasonably good impact properties. It is also suitable for a variety of elevated temperature applications. For maximum wear and abrasion resistance EN19 can be nitrided to give a shallow depth wear resistant case. Flame or induction hardening can give a case hardness of 50 HRc or higher.
Applications
EN19 was originally introduced for the use in the machine tool and motor industries for gears, pinions, shafts, spindles and the like. Later its applications became much more extended and it is now widely used in areas such as the oil and gas industries. EN19 is suitable for applications such as gears, bolts, studs and a wide variety of applications where a good quality high tensile steel grade is suited.
Forging
Preheat carefully, then raise temperature to 850-1200°C for forging. Do not forge below 850°C. After forging cool slowly in still air.
Annealing
Heat the EN19 slowly to 680-700°C. Cool in air.
Hardening
This steel grade is commonly supplied ready heat treated. If further heat treatment is required annealed EN19 should be heated slowly to 860-890°C and after adequate soaking at this temperature quench in oil. Temper as soon as tools reach room temperature.
Tempering
Heat carefully to a suitable temperature selected by reference to a tempering chart or table. Soak at the temperature for 2 hours per 25mm of ruling section, then allow to cool in air. Tempering between 250-375°C is not advised as tempering within this range will reduce the impact value.